diff options
Diffstat (limited to '')
| -rw-r--r-- | pyecsca/ec/curves.py | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/pyecsca/ec/curves.py b/pyecsca/ec/curves.py index bc8329f..aa5e146 100644 --- a/pyecsca/ec/curves.py +++ b/pyecsca/ec/curves.py @@ -1,5 +1,6 @@ import json from os.path import join +from typing import Dict, Union from pkg_resources import resource_listdir, resource_isdir, resource_stream from public import public @@ -41,6 +42,7 @@ def get_params(category: str, name: str, coords: str, infty: bool = True) -> Dom if curve["field"]["type"] == "Binary": raise ValueError("Binary field curves are currently not supported.") + # Get model and param names model: CurveModel field = int(curve["field"]["p"], 16) order = int(curve["order"], 16) @@ -59,29 +61,36 @@ def get_params(category: str, name: str, coords: str, infty: bool = True) -> Dom param_names = ["a", "d"] else: raise ValueError("Unknown curve model.") + + # Check coordinate model name and assumptions if coords not in model.coordinates: raise ValueError("Coordinate model not supported for curve.") coord_model = model.coordinates[coords] params = {name: Mod(int(curve["params"][name], 16), field) for name in param_names} for assumption in coord_model.assumptions: - locals = {} + alocals: Dict[str, Union[Mod, int]] = {} compiled = compile(assumption, "", mode="exec") - exec(compiled, None, locals) - for param, value in locals.items(): + exec(compiled, None, alocals) + for param, value in alocals.items(): if params[param] != value: raise ValueError(f"Coordinate model {coord_model} has an unsatisifed assumption on the {param} parameter (= {value}).") + # Construct the point at infinity + infinity: Point if infty: infinity = InfinityPoint(coord_model) else: - locals = {**params} + ilocals: Dict[str, Union[Mod, int]] = {**params} for line in coord_model.neutral: compiled = compile(line, "", mode="exec") - exec(compiled, None, locals) + exec(compiled, None, ilocals) infinity_coords = {} for coordinate in coord_model.variables: - if coordinate not in locals: + if coordinate not in ilocals: raise ValueError(f"Coordinate model {coord_model} requires infty option.") - infinity_coords[coordinate] = Mod(locals[coordinate], field) + value = ilocals[coordinate] + if isinstance(value, int): + value = Mod(value, field) + infinity_coords[coordinate] = value infinity = Point(coord_model, **infinity_coords) elliptic_curve = EllipticCurve(model, coord_model, field, infinity, params) affine = Point(AffineCoordinateModel(model), x=Mod(int(curve["generator"]["x"], 16), field), |